🏠 New in High Baseline Support: Online status
January 29, 2018
caniuse · mdn · [spec]([‘https://html.spec.whatwg.org/multipage/system-state.html#navigator.online’, ‘https://html.spec.whatwg.org/multipage/indices.html#event-online’])
The navigator.onLine property returns a Boolean for whether the browser is connected to some network (though not necessarily the internet). The online and offline events fire when the connection state changes.